Making aviation history: When a SAAB J37 almost shot down an SR-71

Although 12 Blackbirds were accidentally lost, no Blackbird was ever shot down by the enemy. But, as it turns out, they were not as invulnerable to air-to-air engagements.

In all of the SR-71's history, only one plane could get a radar lock on the fast-moving U.S. Air Force reconnaissance plane as it circled. Interestingly, this was not a cutting-edge Soviet fighter, as you might expect, but a SAAB J37 "Viggen" fighter.

But how?

During the 1980s, one of the SR-71's strategic goals was to follow the "Baltic Express." This required an aircraft to fly through a small gap in international airspace near Sweden.

Few radar systems had a chance to track the SR-71 when it started its missions in the 1960s since the aircraft was at the cutting edge of stealth technology. In the 1980s, however, brand-new and advanced ground sensors could find the plane.

When the SR-71 got close to a predetermined waypoint near Copenhagen, it would activate on Swedish air-defense radar. However, during the "Cold War," Stockholm had a strict policy of neutrality, but it expected the Soviet Union to lead any invasion.

This meant that Sweden would need to at least show some form of reaction to an intrusion into its airspace, even if it had no intention of hostile engagements with Soviet or U.S. aircraft. To this end, Sweden would scramble fighters to intercept.

Throughout the "Cold War," Sweden launched hundreds of Quick Reaction Alert (QRA) flights to snare any unknown aircraft that tried to enter its airspace. The Warsaw Pact and NATO countries that made up the QRA targets mainly passed through Swedish airspace over the Baltic Sea or the Gulf of Bothnia.

Despite being neutral during the "Cold War," Swedish pilots had to develop tactics to intercept foreign aircraft

Initially, when the SR-71 began its "Baltic Express" missions, the SAAB J35F "Draken" ("Dragon") was launched. But, this aging aircraft could not even come close to intercepting one of the most advanced aircraft of the day.

However, Sweden did have a newer interceptor, the iconic SAAB J37 "Viggen." This aircraft was equipped with advanced radar and weapon targeting systems and was more than a match for its contemporaries.

But was it up to the task of handling an intruding SR-71? Swedish pilots believed so, but it would take some lateral thinking.

From their bases, Swedish pilots had to scramble to reach a height slightly below the "Blackbird;" after that, they had to climb while traveling at twice the speed of sound to make a head-on approach to the SR-71.

This might sound insane, but the "Viggen" was outfitted with a "Skyflash" missile capable of a radar lock-on from the front. This was a novelty at the time, as most missile systems were designed to achieve a lock from the rear of a target plane.

Using this combination of technology and tactics, Swedish pilots were confident they could, at least in theory, offer an approaching SR-71 a modicum of worry.

And they were to be validated when in January of 1986, a Swedish pilot in a SAAB J37 "Viggen" fighter, Per-Olof Eldh, managed just that. After taking off and starting a head-on attack, he was able to get himself lined up with the "Blackbird's" path and get full missile lock on the SR-71 coming at him.

Eldh didn't shoot, and the two planes passed by one another, making visual contact and nothing more. Eldh achieved five more successful SR-71 interceptions using this unorthodox tactic, cementing his place in aviation history!